The present invention relates to hitch configurations used in truck beds, particularly beneficial for hitch configurations that also use safety chains. Several existing hitches and original equipment pickups include spaced sockets exposed in the pickup truck bed, such as those disclosed in U.S. Pat. Pub. Nos. 2012/0031940 and 2013/0113181 and U.S. Pat. Nos. 6,065,766, 7,988,176, 7,988,177, 8,215,658, 8,360,458, 8,414,009, each incorporated by reference. The most common socket design involves a generally rectangular or oblong slot which can receive the head of a T-bolt. The sockets are located in the pickup truck bed, generally flush with the face of the truck bed. The sockets are used when the hitch or other device is installed, but the truck bed with its sockets is generally flat so as to be used without interference when the hitch or other device is absent. To use the socket, the T-bolt is inserted vertically (head down) into the socket and then rotated 90° so the long part of the T-bolt head is under the narrower flats 16 of the socket. In one existing socket design, the slot is about one inch wide and about 1.63 inches long, with curved ends so the entire slot fits within a 1.63 inch diameter circle.
Pickup truck owners can utilize the sockets to attach other structures to the pickup truck bed, such as safety chains or tie down structures. Whenever the sockets are used for safety chains or other tie down structures, care must be taken that the T-bolt mating with the socket does not inadvertently rotate about its vertical axis to a position where the head is aligned with the socket opening and the T-bolt can pull free of the socket. U.S. Pat. Nos. 8,215,658, 8,360,452 and Patent Pub. No. 2013/0113181 teach removable safety chain tie down constructions that incorporate structure to prevent the T-bolt from inadvertently rotating about its vertical axis. However, each of these designs are relatively complex, and therefore involve a higher cost of manufacture and are more prone to failure than optimal. Better designs to utilize the sockets are needed.